Solar Payback Calculator — France
Estimate your rooftop autoconsommation system's yearly production, electricity-bill savings, payback time and 20-year net profit. Defaults reflect a typical French rooftop: €1,800/kWp installed, 1,150 kWh/kWp yield, €0.25/kWh TRV electricity and the €0.10/kWh EDF OA feed-in tariff for surplus.
1 · Your system
2 · Live results
yearly = self × price + exported × feed-in20-year net ignores panel degradation, inverter replacement and electricity price changes — see the explainer below.
How solar payback works in France
A rooftop autoconsommation system earns money two ways: every kilowatt-hour you use yourself avoids buying grid electricity at the TRV (~€0.20–0.25/kWh), and surplus you export is bought by EDF under an Obligation d'Achat (OA) contract at a rate fixed for 20 years. There is also a prime à l'autoconsommation (self-consumption bonus) paid per kWp over the first five years — ask your installer for the current amount, as it reduces effective cost.
The formula
| Step | Calculation | Example (defaults) |
|---|---|---|
| Yearly production | kWp × yield | 8 × 1,150 = 9,200 kWh |
| Self-consumed | production × self-use % | 9,200 × 40% = 3,680 kWh |
| Exported | production − self-consumed | 5,520 kWh |
| Yearly value | self × price + exported × feed-in | 3,680 × 0.25 + 5,520 × 0.10 = €1,472 |
| Payback | install cost ÷ yearly value | 14,400 ÷ 1,472 ≈ 9.8 years |
| 20-year net | yearly value × 20 − install cost | €15,040 |
France specifics
- EDF OA contract: surplus is bought at a tariff fixed when you sign, valid for 20 years — currently around €0.10/kWh for small systems. The prime à l'autoconsommation adds a bonus per installed kWp, improving payback beyond what this calculator shows.
- Install cost: French installations run higher (~€1,800/kWp) partly due to qualification requirements (RGE-certified installers are needed for subsidies).
- TRV: the regulated electricity price is the natural benchmark for self-consumed savings; with market contracts, use your actual all-in kWh price.
- Battery: raises self-consumption to 60–80% but adds several thousand euros; re-run the numbers with a higher self-use share and the battery cost included.
Frequently asked questions
How does the EDF OA feed-in tariff work?
EDF (via its Obligation d'Achat) buys your exported surplus at a tariff fixed at contract signing, guaranteed for 20 years. For small residential systems the surplus rate is currently around €0.10/kWh. You sell only the surplus — what you consume yourself is simply never bought from the grid, which is the bigger saving.
What is the prime à l'autoconsommation?
It is a state bonus paid per installed kWp for systems up to 100 kWp, spread over the first five years of operation. The per-kWp amount varies by system size and is revised quarterly, so ask your installer for the current rate. It effectively lowers your installation cost and shortens payback — this calculator doesn't add it automatically, so subtract it from the install cost if you know it.
What self-consumption rate is realistic?
Without a battery, a typical household uses 30–50% of its own production; the rest is exported. With a home battery this rises to 60–80%. Higher daytime usage (home office, heat pump, air conditioning, EV charging at home) pushes the rate up for free.
Do I need an RGE-certified installer?
Not legally required for the installation itself, but an RGE (Reconnu Garant de l'Environnement) certified installer is needed to qualify for most public aid, including the prime à l'autoconsommation. For an 8 kWp rooftop system with EDF OA, using an RGE installer is strongly recommended.
Is a battery worth it in France?
It depends on your numbers. A battery shifts evening consumption to stored solar power, raising self-use from ~40% to ~65%+, but adds €4,000–8,000 to the install cost. Model it: add the battery cost to the installation price and raise the self-consumption share — if the payback time drops, it pays for itself.
Last updated: September 2026.
Disclaimer: True EV Cost tools are for information only and are not professional financial advice. Tariffs, bonuses and electricity prices change — confirm current figures with your installer and EDF OA before investing.